The invention pertains to a cathodic sputtering system with a cathode carrying a target surface to be sputtered; a source of high frequency energy connected to the cathode; and a magnet assembly near the cathode, on the side facing away from the surface to be sputtered. This assembly generates lines of magnetic force, which essentially enter the surface to be sputtered and emerge from it again to form a tunnel-shaped region over a path to be sputtered on the surface of the target. The anode is formed by the substrate to be coated and is located opposite the cathode. The surface to be sputtered and the magnetic device are installed inside an evacuable housing, the magnet assembly being supported so that it can move relative to the cathode under the action of a drive mechanism, the path of the magnets traveling over the surface to be sputtered during one of the cycles of movement.
U.S. Pat. No. 4,444,643 discloses a magnet assembly in a planar magnetron cathode which can be moved around a circular path with respect to the target, for which purpose the magnets are connected non-rotatably to a shaft, which is perpendicular to the surface of the target and driven by a motor. The chamber in which the magnet assembly rotates is sealed off from the outside by a cover, which is made of electrically insulating material, preferably of plastic, while the chamber itself is under atmospheric pressure.
DE-A 2707144 discloses a magnet assembly which can be moved back and forth with respect to a planar target in a plane parallel to the target. In this case, too, the magnet assemblies are installed outside the process chamber and are subject to atmospheric pressure.
DE 44 15 232 discloses a coating system in which a sputter cathode, provided with a set of magnets, is installed inside a coating chamber. The cathode has an electrode connected to negative potential with a set of magnets. A target constituting the material to be sputtered is mounted on the side of the electrode facing away from the set of magnets; on the side of the electrode facing away from the target, a pressure equalization chamber is provided, which has a vacuum connection for creating a negative pressure to counter the negative pressure in the coating chamber.